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Slightly related fun fact: the Futurama theme was based on the song Groening WANTED to use but couldn't secure the rights for. The familiar sounding part starts around 45 seconds in:
Compare and contrast:
Dad and daughter sing Frozen Love is an Open Door
Don Hertzfeld of "My Spoon Is Too Big" made the Simpson's couch gag for "Clown in the Dumps"
Epic Cliff Jumping Hong Kong
Big Lebowski Simpsons Overdub